ARM: legoev3: update boot script to load uEnv.txt and .dtb

This updates the LEGO MINDSTORMS EV3 boot script to try loading a
uEnv.txt file and a da850-lego-ev3.dtb device tree during boot.

Signed-off-by: David Lechner <david@lechnology.com>

diff --git a/board/lego/ev3/README b/board/lego/ev3/README
index a3563732499d3c964e14b302c7dcf7733dc17e1b..da62a649badf60176a9e21d5c2d33a593cd7925d 100644 (file)
--- a/board/lego/ev3/README
+++ b/board/lego/ev3/README
@@ -9,14 +9,34 @@ Booting
 =======
 
 The EV3 contains a bootloader in EEPROM that loads u-boot.bin from address 0x0
-of the spi flash memory. Using the default configuration, u-boot will check to
-see if there is a boot.scr file on the first FAT partition of the mmc. If there
-is, it will run the script and boot the kernel from the uImage file also in
-the FAT partition. Otherwise, it will load a kernel and rootfs from the flash.
-The kernel must be stored at address 0x50000 on the flash and have a maximum
-size of 4MiB. The rootfs must be a squasfs image and stored at 0x450000 in the
-flash and have a maximum size of 10MiB. The flash starting at 0xE50000 is
-reserved for user data.
+of the SPI flash memory (with a size of 256KiB!). Because the EEPROM is read-
+only and it takes care of low level configuration (PLL and DDR), we don't use
+U-Boot to produce an SPL image.
+
+Using the default configuration, U-Boot had a boot scrips that works as follows:
+
+* Check to see if microSD card is present
+* If it is, try to load boot.scr from the first FAT partition
+* If loading boot.scr was successful, run it
+* Otherwise, try loading uEnv.txt
+* If loading uEnv.txt was successful, import it
+* If there is a uenvcmd variable (from uEnv.txt), run it
+* Try to load uImage from the first FAT partition
+* If it was successful, try to load da850-lego-ev3.dtb
+* If loading uImage was successful, boot it (DT is optional)
+* If none of the above was successful, try booting from flash
+
+Suggested Flash Memory Layout
+=============================
+
+The following is based on the default U-Boot configuration:
+
+| Image (file)       | Start Addr. | Max. Size         |
++--------------------+-------------+-------------------+
+| u-boot.bin         |         0x0 |  0x40000 (256KiB) |
+| da850-lego-ev3.dtb |     0x40000 |  0x10000 (64KiB)  |
+| uImage             |     0x50000 | 0x400000 (4MiB)   |
+| rootfs (squashfs)  |    0x450000 | 0xa00000 (10MiB)  |
 
 Writing image to flash
 ======================

diff --git a/include/configs/legoev3.h b/include/configs/legoev3.h
index 9eb95bc030f45ad96df4c702cac55b5594c011a2..7a0511f88e6d1f47041295dcd3286d341aadb4b2 100644 (file)
--- a/include/configs/legoev3.h
+++ b/include/configs/legoev3.h
@@ -84,34 +84,60 @@
                "if run loadbootscr; then " \
                        "run bootscript; " \
                "else " \
+                       "if run loadbootenv; then " \
+                               "echo Loaded env from ${bootenvfile};" \
+                               "run importbootenv;" \
+                       "fi;" \
+                       "if test -n $uenvcmd; then " \
+                               "echo Running uenvcmd...;" \
+                               "run uenvcmd;" \
+                       "fi;" \
                        "if run loadimage; then " \
                                "run mmcargs; " \
+                               "if run loadfdt; then " \
+                                       "echo Using ${fdtfile}...;" \
+                                       "run fdtfixup; " \
+                                       "run fdtboot; "\
+                               "fi; " \
                                "run mmcboot; " \
-                       "else " \
-                               "run flashargs; " \
-                               "run flashboot; " \
                        "fi; " \
                "fi; " \
-       "else " \
-               "run flashargs; " \
-               "run flashboot; " \
-       "fi"
+       "fi; "\
+       "run flashargs; " \
+       "run flashboot"
 #define CONFIG_EXTRA_ENV_SETTINGS \
+       "bootenvfile=uEnv.txt\0" \
+       "fdtfile=da850-lego-ev3.dtb\0" \
        "memsize=64M\0" \
        "filesyssize=10M\0" \
        "verify=n\0" \
        "console=ttyS1,115200n8\0" \
        "bootscraddr=0xC0600000\0" \
+       "fdtaddr=0xC0600000\0" \
        "loadaddr=0xC0007FC0\0" \
        "filesysaddr=0xC1180000\0" \
        "fwupdateboot=mw 0xFFFF1FFC 0x5555AAAA; reset\0" \
-       "mmcargs=setenv bootargs mem=${memsize} console=${console} root=/dev/mmcblk0p2 rw rootwait lpj=747520\0" \
+       "importbootenv=echo Importing environment...; " \
+               "env import -t ${loadaddr} ${filesize}\0" \
+       "loadbootenv=fatload mmc 0 ${loadaddr} ${bootenvfile}\0" \
+       "mmcargs=setenv bootargs console=${console} root=/dev/mmcblk0p2 rw " \
+               "rootwait ${optargs}\0" \
        "mmcboot=bootm ${loadaddr}\0" \
-       "flashargs=setenv bootargs mem=${memsize} initrd=${filesysaddr},${filesyssize} root=/dev/ram0 rw rootfstype=squashfs console=${console} lpj=747520\0" \
-       "flashboot=sf probe 0; sf read ${loadaddr} 0x50000 0x400000; sf read ${filesysaddr} 0x450000 0xA00000; bootm ${loadaddr}\0" \
+       "flashargs=setenv bootargs initrd=${filesysaddr},${filesyssize} " \
+               "root=/dev/ram0 rw rootfstype=squashfs console=${console} " \
+               "${optargs}\0" \
+       "flashboot=sf probe 0; " \
+               "sf read ${fdtaddr} 0x40000 0x10000; " \
+               "sf read ${loadaddr} 0x50000 0x400000; " \
+               "sf read ${filesysaddr} 0x450000 0xA00000; " \
+               "run fdtfixup; " \
+               "run fdtboot\0" \
        "loadimage=fatload mmc 0 ${loadaddr} uImage\0" \
+       "loadfdt=fatload mmc 0 ${fdtaddr} ${fdtfile}\0" \
+       "fdtfixup=fdt addr ${fdtaddr}; fdt resize; fdt chosen\0" \
+       "fdtboot=bootm ${loadaddr} - ${fdtaddr}\0" \
        "loadbootscr=fatload mmc 0 ${bootscraddr} boot.scr\0" \
-       "bootscript=source ${bootscraddr}\0" \
+       "bootscript=source ${bootscraddr}\0"
 
 #ifdef CONFIG_CMD_BDI
 #define CONFIG_CLOCKS